Associations of dietary quality and physical activity with glycemic control in patients with type 2 diabetes: the moderating role of trait mindfulness.

Background: Dietary quality and physical activity are fundamental components of glycemic management in patients with type 2 diabetes mellitus (T2DM). However, glycemic responses to lifestyle behaviors may vary across individuals, suggesting a potential role of psychological self-regulation traits. This study aimed to assess the associations of dietary quality and physical activity with glycemic indicators among hospitalized patients with T2DM and to test whether the Act with Awareness dimension of trait mindfulness moderated these associations using interaction models. Methods: This cross-sectional study included 400 hospitalized patients with T2DM at the Second Affiliated Hospital of Xuzhou Medical University between December 2023 and June 2025. Dietary quality was assessed using a structured dietary score, and physical activity was evaluated according to self-reported weekly exercise duration. Trait mindfulness was measured using the Five Facet Mindfulness Questionnaire. The primary outcomes were glycated hemoglobin (HbA1c) and fasting blood glucose (FBG), both of which were natural log-transformed before regression analyses. Multivariable linear regression models were used to estimate the associations of dietary quality and physical activity with log-transformed HbA1c and FBG. Multiplicative interaction terms were then included to test the moderating role of Act with Awareness, with adjustment for demographic characteristics, lifestyle factors, BMI, diabetes duration, sleep, comorbidities, medication use, and insulin use. Results: In fully adjusted models, higher dietary scores were associated with lower log-transformed HbA1c (β = -0.019, 95% CI: -0.032 to -0.005; P = 0.008) and FBG (β = -0.023, 95% CI: -0.042 to -0.003; P = 0.022). Physical activity scores were negatively associated with HbA1c (β = -0.002, 95% CI: -0.004 to 0.000; P = 0.034), but not with FBG. Significant interactions were observed between Act with Awareness and dietary score for both HbA1c and FBG, and between Act with Awareness and physical activity score for HbA1c. Conclusion: Better dietary quality and higher physical activity were associated with more favorable glycemic indicators among hospitalized patients with T2DM. Act with Awareness may modify the strength of these associations. Given the cross-sectional design, these findings should be interpreted as observational associations rather than causal relationships.